/**
 * 1.是什么
 *    一旦我们重启应用，Sentinel规则将消失，生产环境需要将配置规则进行持久化
 *
 * 2.如何解决
 *    将限流配置规则持久化进Nacos保存，只要刷新8401某个rest地址，sentinel控制台的流控规则就能看到，只要Nacos里面的配置不删除，
 *  针对8401上Sentinel上的流控规则持续有效
 *
 * 1.步骤一
 * <!--SpringCloud ailibaba sentinel-datasource-nacos 后续做持久化用到-->
 * <dependency>
 *     <groupId>com.alibaba.csp</groupId>
 *     <artifactId>sentinel-datasource-nacos</artifactId>
 * </dependency>
 *
 * ２.步骤二
 *      pom修改
 *      datasource:
 *         ds1:
 *           nacos:
 *             server-addr: localhost:8848
 *             dataId: cloudalibaba-sentinel-service
 *             groupId: DEFAULT_GROUP
 *             data-type: json
 *             rule-type: flow
 *
 *  3.步骤三
 *  nacos添加配置
 *  [
 *     {
 *          "resource": "/retaLimit/byUrl",
 *          "limitApp": "default",
 *          "grade":   1,
 *          "count":   1,
 *          "strategy": 0,
 *          "controlBehavior": 0,
 *          "clusterMode": false
 *     }
 * ]
 */